Perception may be thought of as the orientation of your internal state of mind.

The common theory of perception is based on the philosophy that there is an external world that is real to which we react - however that is an Aristotlean (look him up you stupid lazykids) dictatorship which is imposed on the masses who reside inside the educational system and have come wired up to it like humans wired up to the matrix.

In reality, considering the state of perception it is perfectly possible to perceive virtually anything, and believe any construct or effect that arises from the actions which inevitably arise as consequences of those perceptions.